[ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty2. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.3' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 33.328803] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 33.340358] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program [ 33.398299] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 33.407680] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 33.437571] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program [ 33.446885] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 33.478733] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 33.487847] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program [ 33.527979] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 33.537217] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 38.344929] nla_parse: 226 callbacks suppressed [ 38.344937] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.363348] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program [ 38.409892] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.423549] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.470029] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.482386] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program [ 38.521006] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.532246] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.580733] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 38.590954] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 43.388518] nla_parse: 216 callbacks suppressed [ 43.388527] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 43.402168] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program [ 43.459415] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 43.470908] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 43.507805] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 43.518111] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program [ 43.569005] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 43.580618] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program [ 43.639162] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. [ 43.649703] netlink: 4 bytes leftover after parsing attributes in process `syz-executor415'. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 46.130911] ================================================================== [ 46.138687] BUG: KASAN: use-after-free in refcount_dec_not_one+0x71/0x1d0 [ 46.145616] Read of size 4 at addr ffff8880aaa98198 by task syz-executor415/10134 [ 46.153249] [ 46.154870] CPU: 0 PID: 10134 Comm: syz-executor415 Not tainted 4.19.211-syzkaller #0 [ 46.162822] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.172699] Call Trace: [ 46.175288] dump_stack+0x1fc/0x2ef [ 46.178929] print_address_description.cold+0x54/0x219 [ 46.184234] kasan_report_error.cold+0x8a/0x1b9 [ 46.188992] ? refcount_dec_not_one+0x71/0x1d0 [ 46.193572] kasan_report+0x8f/0xa0 [ 46.197551] ? refcount_dec_not_one+0x71/0x1d0 [ 46.202135] refcount_dec_not_one+0x71/0x1d0 [ 46.206638] ? refcount_dec_and_test_checked+0x20/0x20 [ 46.211928] ? nbd_config_put+0x5da/0x870 [ 46.216073] refcount_dec_and_mutex_lock+0x1c/0x80 [ 46.221027] nbd_genl_connect+0x11ee/0x1630 [ 46.225334] ? nbd_xmit_timeout+0x730/0x730 [ 46.229650] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 46.234858] ? validate_nla+0x270/0x820 [ 46.238820] ? nla_parse+0x1b2/0x290 [ 46.242524] genl_family_rcv_msg+0x642/0xc40 [ 46.246934] ? genl_rcv+0x40/0x40 [ 46.250377] ? genl_rcv_msg+0x12f/0x160 [ 46.254342] ? mutex_trylock+0x1a0/0x1a0 [ 46.258479] ? __radix_tree_lookup+0x216/0x370 [ 46.263062] genl_rcv_msg+0xbf/0x160 [ 46.266778] netlink_rcv_skb+0x160/0x440 [ 46.270835] ? genl_family_rcv_msg+0xc40/0xc40 [ 46.275426] ? netlink_ack+0xae0/0xae0 [ 46.279312] ? genl_rcv+0x15/0x40 [ 46.282750] genl_rcv+0x24/0x40 [ 46.286009] netlink_unicast+0x4d5/0x690 [ 46.290054] ? netlink_sendskb+0x110/0x110 [ 46.294273] ? _copy_from_iter_full+0x229/0x7c0 [ 46.298926] ? __phys_addr_symbol+0x2c/0x70 [ 46.303236] ? __check_object_size+0x17b/0x3e0 [ 46.307802] netlink_sendmsg+0x6c3/0xc50 [ 46.311853] ? aa_af_perm+0x230/0x230 [ 46.315646] ? nlmsg_notify+0x1f0/0x1f0 [ 46.319607] ? kernel_recvmsg+0x220/0x220 [ 46.323752] ? nlmsg_notify+0x1f0/0x1f0 [ 46.327722] sock_sendmsg+0xc3/0x120 [ 46.331434] ___sys_sendmsg+0x7bb/0x8e0 [ 46.335392] ? copy_msghdr_from_user+0x440/0x440 [ 46.340132] ? netlink_dump+0xc10/0xc10 [ 46.344090] ? nlmsg_notify+0x1f0/0x1f0 [ 46.348051] ? security_socket_recvmsg+0x8f/0xc0 [ 46.352791] ? __sys_recvfrom+0x2cd/0x3a0 [ 46.356919] ? __ia32_sys_send+0x100/0x100 [ 46.361142] ? __fdget+0x1a0/0x230 [ 46.364667] __x64_sys_sendmsg+0x132/0x220 [ 46.368892] ? __sys_sendmsg+0x1b0/0x1b0 [ 46.372962] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 46.378312] ? trace_hardirqs_off_caller+0x6e/0x210 [ 46.383320] ? do_syscall_64+0x21/0x620 [ 46.387285] do_syscall_64+0xf9/0x620 [ 46.391094] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.396268] RIP: 0033:0x7f65dd604a29 [ 46.399976] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 46.418870] RSP: 002b:00007ffda7131398 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 46.426571] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f65dd604a29 [ 46.433836] RDX: 0000000024000040 RSI: 0000000020000380 RDI: 0000000000000003 [ 46.441091] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 46.448344] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000b269 [ 46.455599] R13: 00007ffda71313ac R14: 00007ffda71313c0 R15: 00007ffda71313b0 [ 46.462917] [ 46.464536] Allocated by task 10121: [ 46.468268] kmem_cache_alloc_trace+0x12f/0x380 [ 46.472930] nbd_dev_add+0x44/0x890 [ 46.476550] nbd_genl_connect+0x4cc/0x1630 [ 46.480769] genl_family_rcv_msg+0x642/0xc40 [ 46.485183] genl_rcv_msg+0xbf/0x160 [ 46.488878] netlink_rcv_skb+0x160/0x440 [ 46.492926] genl_rcv+0x24/0x40 [ 46.496187] netlink_unicast+0x4d5/0x690 [ 46.500234] netlink_sendmsg+0x6c3/0xc50 [ 46.504277] sock_sendmsg+0xc3/0x120 [ 46.507971] ___sys_sendmsg+0x7bb/0x8e0 [ 46.511942] __x64_sys_sendmsg+0x132/0x220 [ 46.516178] do_syscall_64+0xf9/0x620 [ 46.519990] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.525163] [ 46.526769] Freed by task 10134: [ 46.530120] kfree+0xcc/0x210 [ 46.533207] nbd_put.part.0+0xfe/0x140 [ 46.537082] nbd_config_put+0x6a0/0x870 [ 46.541059] nbd_genl_connect+0x11bb/0x1630 [ 46.545383] genl_family_rcv_msg+0x642/0xc40 [ 46.549785] genl_rcv_msg+0xbf/0x160 [ 46.553505] netlink_rcv_skb+0x160/0x440 [ 46.557547] genl_rcv+0x24/0x40 [ 46.560811] netlink_unicast+0x4d5/0x690 [ 46.564854] netlink_sendmsg+0x6c3/0xc50 [ 46.568896] sock_sendmsg+0xc3/0x120 [ 46.572592] ___sys_sendmsg+0x7bb/0x8e0 [ 46.576553] __x64_sys_sendmsg+0x132/0x220 [ 46.580779] do_syscall_64+0xf9/0x620 [ 46.584594] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.589815] [ 46.591424] The buggy address belongs to the object at ffff8880aaa980c0 [ 46.591424] which belongs to the cache kmalloc-512 of size 512 [ 46.604063] The buggy address is located 216 bytes inside of [ 46.604063] 512-byte region [ffff8880aaa980c0, ffff8880aaa982c0) [ 46.615931] The buggy address belongs to the page: [ 46.620845] page:ffffea0002aaa600 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0 [ 46.628967] flags: 0xfff00000000100(slab) [ 46.633114] raw: 00fff00000000100 ffffea0002a126c8 ffffea0002a2b288 ffff88813bff0940 [ 46.640980] raw: 0000000000000000 ffff8880aaa980c0 0000000100000006 0000000000000000 [ 46.648845] page dumped because: kasan: bad access detected [ 46.654581] [ 46.656386] Memory state around the buggy address: [ 46.661320] ffff8880aaa98080: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 46.668672] ffff8880aaa98100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.676043] >ffff8880aaa98180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.683400] ^ [ 46.687550] ffff8880aaa98200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.694923] ffff8880aaa98280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 46.702266] ================================================================== [ 46.709609] Disabling lock debugging due to kernel taint [ 46.716574] Kernel panic - not syncing: panic_on_warn set ... [ 46.716574] [ 46.723950] CPU: 0 PID: 10134 Comm: syz-executor415 Tainted: G B 4.19.211-syzkaller #0 [ 46.733308] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.742659] Call Trace: [ 46.745252] dump_stack+0x1fc/0x2ef [ 46.748886] panic+0x26a/0x50e [ 46.752086] ? __warn_printk+0xf3/0xf3 [ 46.755977] ? preempt_schedule_common+0x45/0xc0 [ 46.760729] ? ___preempt_schedule+0x16/0x18 [ 46.765147] ? trace_hardirqs_on+0x55/0x210 [ 46.769462] kasan_end_report+0x43/0x49 [ 46.773444] kasan_report_error.cold+0xa7/0x1b9 [ 46.778098] ? refcount_dec_not_one+0x71/0x1d0 [ 46.782761] kasan_report+0x8f/0xa0 [ 46.786411] ? refcount_dec_not_one+0x71/0x1d0 [ 46.791000] refcount_dec_not_one+0x71/0x1d0 [ 46.795392] ? refcount_dec_and_test_checked+0x20/0x20 [ 46.800665] ? nbd_config_put+0x5da/0x870 [ 46.804819] refcount_dec_and_mutex_lock+0x1c/0x80 [ 46.809733] nbd_genl_connect+0x11ee/0x1630 [ 46.814038] ? nbd_xmit_timeout+0x730/0x730 [ 46.818341] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 46.823513] ? validate_nla+0x270/0x820 [ 46.827468] ? nla_parse+0x1b2/0x290 [ 46.831175] genl_family_rcv_msg+0x642/0xc40 [ 46.835572] ? genl_rcv+0x40/0x40 [ 46.839019] ? genl_rcv_msg+0x12f/0x160 [ 46.842981] ? mutex_trylock+0x1a0/0x1a0 [ 46.847048] ? __radix_tree_lookup+0x216/0x370 [ 46.851618] genl_rcv_msg+0xbf/0x160 [ 46.855315] netlink_rcv_skb+0x160/0x440 [ 46.859357] ? genl_family_rcv_msg+0xc40/0xc40 [ 46.863935] ? netlink_ack+0xae0/0xae0 [ 46.867810] ? genl_rcv+0x15/0x40 [ 46.871253] genl_rcv+0x24/0x40 [ 46.874544] netlink_unicast+0x4d5/0x690 [ 46.878586] ? netlink_sendskb+0x110/0x110 [ 46.882802] ? _copy_from_iter_full+0x229/0x7c0 [ 46.887452] ? __phys_addr_symbol+0x2c/0x70 [ 46.891852] ? __check_object_size+0x17b/0x3e0 [ 46.896431] netlink_sendmsg+0x6c3/0xc50 [ 46.900487] ? aa_af_perm+0x230/0x230 [ 46.904269] ? nlmsg_notify+0x1f0/0x1f0 [ 46.908221] ? kernel_recvmsg+0x220/0x220 [ 46.912362] ? nlmsg_notify+0x1f0/0x1f0 [ 46.916335] sock_sendmsg+0xc3/0x120 [ 46.920049] ___sys_sendmsg+0x7bb/0x8e0 [ 46.924006] ? copy_msghdr_from_user+0x440/0x440 [ 46.928746] ? netlink_dump+0xc10/0xc10 [ 46.932714] ? nlmsg_notify+0x1f0/0x1f0 [ 46.936693] ? security_socket_recvmsg+0x8f/0xc0 [ 46.941442] ? __sys_recvfrom+0x2cd/0x3a0 [ 46.945572] ? __ia32_sys_send+0x100/0x100 [ 46.949804] ? __fdget+0x1a0/0x230 [ 46.953328] __x64_sys_sendmsg+0x132/0x220 [ 46.957545] ? __sys_sendmsg+0x1b0/0x1b0 [ 46.961591] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 46.966952] ? trace_hardirqs_off_caller+0x6e/0x210 [ 46.971951] ? do_syscall_64+0x21/0x620 [ 46.975909] do_syscall_64+0xf9/0x620 [ 46.979710] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.984887] RIP: 0033:0x7f65dd604a29 [ 46.988583] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 47.007469] RSP: 002b:00007ffda7131398 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 47.015189] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f65dd604a29 [ 47.022447] RDX: 0000000024000040 RSI: 0000000020000380 RDI: 0000000000000003 [ 47.029697] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 47.036948] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000b269 [ 47.044196] R13: 00007ffda71313ac R14: 00007ffda71313c0 R15: 00007ffda71313b0 [ 47.051539] Kernel Offset: disabled [ 47.055150] Rebooting in 86400 seconds..